Windows 7's built-in RDP / "Remote Desktop Connection" tool => works with audio, but there are crackles/pops, even with this trick and this one.
UltraVNC => no audio support
TightVNC => no audio support
RealVNC Enterprise => very good audio support, no lag / no crackle, high quality ; but not free
Is there a "remote desktop" software for Windows that both:
has good audio support
is open-source or freeware